Agricultural liquid application nozzle, system, and method

ABSTRACT

A spraying nozzle, system, and associated methods for applying a liquid to foliage are provided. A container having an opening supplies liquid to be sprayed to a nozzle that includes a spray tip at an upstream end. The nozzle is made of an inert material, and a magnet is affixed adjacent the spray tip&#39;s orifice along the liquid pathway. The liquid is pumped out of the container, passing by and contacting the magnet, which affects the liquid droplets by orienting the dipoles of the molecules comprising the liquid. This serves to reduce the droplet size owing to mutual repulsion, creating a &#34;cloud&#34; of spray. The smaller droplets are better able to penetrate smaller spaces in the foliage such as insect habitats and difficult-to-access foliage pockets. The transient magnetization also increases the attraction of the droplets for the foliage, which thereby further increases the efficiency of spraying and coverage achieved.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to systems and methods for applyingliquids to foliage and, more particularly, to such systems and methodsemploying liquids under pressure through a nozzle.

2. Description of Related Art

The spraying of crops and other foliage is known to be accomplished withthe use of nozzles through which liquid under pressure is forced anddirected to the desired target area, typically the leaves. Concentratesprayers have difficulties owing to impingement and even distribution ofspray particles throughout large target areas. Low-volume sprayersoffered some promise in the reduction of the use of spray chemicals, butposed problems of drift and consequent potential contamination of crops,animals, and people. Electrostatic sprayers addressed the drift problembut have proved too complicated and impractical for grower use.

In order to optimize application efficiency, systems have been devisedfor sensing the location of the foliage and controlling the direction ofthe spray toward the sensed location. Such systems have lessened theamount of chemical required to be sprayed but still did not address theproblem of drift, which can amount to 50% loss of sprayed chemical.

The charging of sprayed liquid has been disclosed by Ward (U.S. Pat. No.3,195,264), Inculet et al. (U.S. Pat. Nos. 4,666,089 and 4,673,132),Burls et al. (U.S. Pat. No. 4,762,274), Lunzer (U.S. Pat. No.5,080,289), and Wilson et al. (U.S. Pat. No. 5,228,621). Amagnetic-field-generating nozzle for atomizing a molten metal streaminto a particle spray is taught by Muench et al. (U.S. Pat. No.4,925,103). The use of a permanent magnet to increase the efficiency ofapplying paint has been disclosed by Romanov (SU 1212-606-A). In thisdevice the magnet is outside the spray nozzle and does not come intodirect contact with the paint. Further, the sprayer components are notinert.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a spraynozzle for applying liquid to foliage.

It is an additional object to provide an agricultural spraying systemincorporating such a nozzle.

It is a further object to provide a method for spraying foliage.

It is another object to provide a method of improving the efficiency ofan agricultural spraying process.

It is yet an additional object to provide a nozzle for reducing theparticle size of droplets emerging from a spraying apparatus.

It is yet a further object to provide a method for reducing the particlesize of droplets emerging from a spraying apparatus.

It is yet another object to provide a spraying system having increasedspecificity for living foliage.

An additional object is to provide a method of reducing fouling of linesused to carry liquid to be sprayed.

Another object is to reduce the quantity of liquid required to achieve adesired coverage of foliage to be sprayed.

These objects and others are attained by the present invention, aspraying nozzle, system, and associated methods for applying a liquid tofoliage. Throughout the word foliage is to be construed to includeliving plant material, including, but not limited to, leaves, stems,branches, and trunks. The system comprises a container that is adaptedfor holding a liquid. The container has an opening. The system alsocomprises a nozzle that includes a spray tip at an upstream end that hasan orifice. The nozzle comprises an inert material and a magnet that isaffixed adjacent the orifice along the liquid pathway.

A line having a lumen is affixable at an upstream end to the containerand to the nozzle at a downstream end. The lumen is in communicationwith the container's opening and also with the to nozzle orifice.

Means are provided in the system for pumping liquid from the containerthrough the line and out the nozzle orifice. The liquid, on its way outthe nozzle orifice, passes by and contacts the magnet and is subject tothe magnetic field, which affects the liquid droplets by orienting thedipoles of the molecules comprising the liquid, which serves to reducethe droplet size owing to mutual repulsion, creating a “cloud” of spray.The smaller droplets are better able to penetrate smaller spaces in thefoliage such as insect habitats and difficult-to-access foliage pockets.The temporary magnetization also increases the attraction of thedroplets for the foliage, which thereby further increases the efficiencyof spraying and coverage achieved.

The features that characterize the invention, both as to organizationand method of operation, together with further objects and advantagesthereof, will be better understood from the following description usedin conjunction with the accompanying drawing. It is to be expresslyunderstood that the drawing is for the purpose of illustration anddescription and is not intended as a definition of the limits of theinvention. These and other objects attained, and advantages offered, bythe present invention will become more fully apparent as the descriptionthat now follows is read in conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of the agricultural spraying system of thepresent invention.

FIG. 2 is an exploded view of a first embodiment of the spray nozzle.

FIG. 3 is an exploded view of a second embodiment of the spray nozzle.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A description of the preferred embodiments of the present invention willnow be presented with reference to FIGS. 1-3.

The agricultural spraying system 10 of the present invention in apreferred embodiment includes a vehicle 90 that is drivable adjacentrows of crops 91, typically along pathways 92 between rows of crops suchas trees 93. This is not intended as a limitation, however, asindividual plants, trees, or bushes can also be sprayed with the system10. Means 94 for sensing a location of foliage such as is known in theart may also be positioned on the vehicle 90. Such means 94 may also beadapted to control the spraying nozzles to be described herein forpreferentially spraying the sensed location of the crops 91 desired tobe sprayed.

The vehicle 90 has removably affixed thereto a container 12 for holdingthe liquid 14 to be sprayed, which may comprise, for example, a biocideor a fertilizer. Preferably the container 12 comprises a magneticallyinert material such as a plastic, and may contain means for agitating orstirring the container's contents, which may be desirable if, forexample, the contents do not readily stay in solution.

The container 12 has an opening 16 into which is coupled a first line 18leading to a pump 19, which is mounted on the vehicle 90. From the pump19 lead a plurality of lines 20 for distributing liquid 14 to aplurality of nozzles 22 (52 in a second embodiment, FIG. 3), acrosswhich air is directed between vanes 23 by at least ore fan (not shown)for atomizing the liquid 14. Fans such as are known in the art may beemployed as desirable for a particular crop, such as fans ranging from24 to 48 inches. It is preferred to provide entrained turbulent air at100+ mph, although this is not intended as a limitation.

Each nozzle 22,52 in a first (FIG. 2) and a second embodiment (FIG. 3),respectively, comprises a nozzle body 26,56 that has a coupler forcoupling to a line 20 such as is well known in the art at an upstreamend 27,57 and a lumen 28,58. The upstream end exterior surface 29,59 maycomprise, for example, a hex face. At the downstream end 30,60 are anexternal, male threaded portion 31,61 and an internal, female threadedportion 32,62.

Threadable into the internal threaded portion 32,62 of the nozzle body26,56 is a generally cylindrical strainer 33,63 having a lumen 34,64that contains a filter such as a 100-mesh filter (not shown) forfiltering liquid passing through the lumen 34,64. The lumen 34,64, whenthe strainer 33,63 is screwed into the nozzle body 26,56, is incommunication with the nozzle body's lumen 28,58. The strainer 33,63also has a head 35,65 at the downstream end.

A spray tip 36,66 is positionable with the strainer head 35,65 at anupstream end, and has a lumen 38,68 in communication with the strainer'slumen 34,64 leading to an orifice 39,69 configured to disperse liquidpassing therethrough. The first embodiment of the spray tip 36 comprisesa slotted member for producing a generally planar spray, while thesecond embodiment of the spray tip 66 includes a generally toroidal core361 positionable in abutting relation to the strainer head 65, followeddownstream by a disc 362 positionable downstream of the core 361. Thelumina 363,68 of these members, respectively, are configured forproducing a desired spray pattern, such as is offered by PrecisionLumark Nozzles (Precision Fitting and Valve Co., Inc., Farmington,Minn.). Many such nozzles are known in the art, however, and these arenot intended as limitations on the present invention.

A cap 40,70 anchors the spray tip 36,66 and strainer 33,63 in engagementwith the nozzle body 26,56 and has a lumen 41,71 in communication withthe spray tip's orifice 39,69. The lumen's inner surface comprises afemale threaded portion 42,72 for engaging the nozzle body's malethreaded portion 31,61. This portion of the lumen 41,71 is sufficientlylarge to encompass the strainer 33,63 and spray tip 36,66 and otherintervening elements, and thus hold them in place when the threadedportions 42,72;31,61 are engaged.

Preferably the nozzle body 26,56, strainer 33,63, spray tip 36,66, andcap 40,70 comprise an inert material, such as a ceramic, carbide, orpolyglass, although these materials are not intended as limitations.

The nozzle 22,52 additionally comprises a magnet positionable adjacentthe spray tip 36,66. In the first embodiment 22 a plurality of barmagnets 43 are positionable in abutting relation to and within thestrainer 33. The bar magnets 43 each has a positive/negative axis, andthe negative pole 44 faces in a common direction for all bar magnets 43,preferably toward the spray tip's orifice 39.

In the second embodiment 52 a toroidal magnet 73 is placed between thecore 361 and the disc 362, with the negative face 74 toward the spraytip's orifice 69. Alternatively, the toroidal magnet may have an outerdiameter dimensioned for placement within the strainer 63 upstream ofthe head 65. The toroidal magnet 73 may also comprise a plurality oftoroidal magnets 73,73′,73″ stacked so that their polarities are alignedin a common direction. An exemplary toroidal magnet 73 comprises aneodymium ring (The Magnet Source, Miami, Fla.), such as a ⅜-in. “donut”magnet, although this is not intended as a limitation.

In addition to placing a magnet or plurality of magnets adjacent thenozzle, magnets 43,73 may also be placed in the lumen of the line(s) 20,in the liquid container 12 upstream of the line(s) 20, and/or also onthe spray vanes. In any placement, however, it is preferred that themagnets are in direct contact with the liquid pathway.

Test Results

A controlled test was performed by the University of Florida CooperativeExtension Service Institute of Food and Agricultural Sciences at afernery in Volusia County, Fla. As is shown in Table 1, which is acompilation of experiments undertaken over a six-week period, thepercent of leaves infected has been reduced (29%) with the use of thesystem and method of the present invention. Even more dramatic is thereduction in average percent of leaf area damaged (73%).

TABLE 1 Data from Controlled Experiment on Results of Spraying a Crop ofFerns with the System of the Present Invention Leaf area Land areaLeaves sampled Leaves infected (%) damaged (%) Control 115 23.48 1.43Expt. 167 24.55 0.75 Control 107 13.0 1.58 Expt. 123 16.9 0.66 Control107 14.0 0.96 Expt. 128 7.03 0.17 Control 135 14.81 0.21 Expt. 129 14.730.46 Control 136 24.3 2.89 Expt. 127 11.02 0.31 Control 134 36.57 6.77Expt. 129 15.50 1.35 Control (avg.) 21.03 2.31 Expt. (avg.) 14.96 0.62Avg. dif. (%) −29% −73%

Table 2 shows results using the present invention as compared with otherpublished data.

TABLE 2 Published Data on Agricultural Coverage with Conventional AirBlast Sprayer vs. Present Invention Trees, 35′ high^(a) Helicopter FMCPTO 57% FMC Engine 92% Magnetic 93% Ratio spray coverage, top to bottomof trees Conventional air blast sprayer^(b) 51% Magnetic 97% Variationof control of fungi on avocadoes w. copper Conventional^(c) 50% MagneticEffect of growth regulators (Giberilum) - % increase over controlConventional^(d) 65% Magnetic 130% Percentage of droplet according tosize found in insect microhabitat^(e) 100 μm 0%  50 μm 99%  30 μm 98%Savings on chemical over conventional sprayer 50-75% Coverage efficiencyConventional sprayer 44% Magnetic 96% ^(a)University of California,Haire. ^(b)Guelph University, Frank. ^(c)University of Florida,McMillan. ^(d)FMC, Lane. ^(e)Michigan State University, Ayers.

It is believed that the transiently magnetized particles are attractedto the living portions of the plants toward which they are aimed,including the leaves, stems, and trunks. It is preferable to tailor theforce field of the spray particles to the intended target, with 30 μmbelieved best for reaching microhabitats of insects.

Tests have been performed with the use of fluorescent dye incorporatedin the sprayed liquid to determine coverage and drift. These testsresulted in a finding that 98% of the magnetized spray reaches andadheres to foliage surfaces, on both top and bottom surfaces thereof. Awind of 12 mph did not substantially affect spray drift. No spray wasfound on the ground, and the 2% not found on the target foliage couldnot be accounted for.

From the data collected in the tables it may be seen that the magneticsystem and methods of the present invention confer a number ofadvantages that are economically and environmentally beneficial:coverage is increased, enabling a reduction in amount of chemical used;penetration into insect microhabitats is increased owing to a decreasein droplet size emitted by the magnetic sprayer; growth improvement isenhanced owing to increased coverage and penetration; sprayed substancesare found primarily on foliage and not on the ground, as indicated byinclusion of fluorescent dye in the sprayed liquid.

In summary, then, the tests have proved that the magnetic spray isadvantageous over conventional spraying apparatus owing to only 2%drift, 98% coverage, and 75% reduced chemical, resulting in bettercontrol of pests. Also, fewer spray applications are required, as fieldtests showed that the interval between spray applications can beincreased without lessening the quality of the crop. Such an intervalcan be up to three times as long as typically used.

It may be appreciated by one skilled in the art that additionalembodiments may be contemplated, including other orientations of amagnet or plurality of magnets on the nozzle or along other portions ofthe line.

In the foregoing description, certain terms have been used for brevity,clarity, and understanding, but no unnecessary limitations are to beimplied therefrom beyond the requirements of the prior art, because suchwords are used for description purposes herein and are intended to bebroadly construed. Moreover, the embodiments of the apparatusillustrated and described herein are by way of example, and the scope ofthe invention is not limited to the exact details of construction.

Having now described the invention, the construction, the operation anduse of preferred embodiment thereof, and the advantageous new and usefulresults obtained thereby, the new and useful constructions, andreasonable mechanical equivalents thereof obvious to those skilled inthe art, are set forth in the appended claims.

What is claimed is:
 1. A nozzle for applying liquid under pressure tofoliage comprising: a nozzle body having means for coupling to a line atan upstream end and a lumen; a spray tip at a downstream end having anorifice; means for mating the nozzle body with the spray tip, the matingmeans comprising a strainer comprising a generally cylindrical portionhaving a strainer lumen in communication with the nozzle body lumen andthe spray tip orifice and the strainer further comprising means forfiltering liquid passing through the strainer lumen; and a magnetpositionable adjacent the spray tip along a liquid pathway comprising atoroidal element dimensioned to fit within the strainer lumen; whereinthe spray tip, the coupling means, and the nozzle body comprise asubstantially inert material.
 2. The nozzle recited in claim 1, whereinthe magnet comprises a plurality of toroidal elements, each having anegative face and a positive face, the hole extending therebetween, thenegative faces all facing in a common direction.
 3. The nozzle recitedin claim 1, further comprising a cap having means for anchoring thespray tip and strainer in engagement with the nozzle body and furtherhaving a lumen in communication with the spray tip orifice.
 4. Thenozzle recited in claim 1, wherein the magnet comprises a generallytoroidal element positionable between a downstream end of the strainerand an upstream end of the spray tip, the toroidal element having a holetherethrough in communication with the strainer lumen and the spray tiporifice.
 5. A nozzle for applying liquid under pressure to foliagecomprising: a nozzle body having means for coupling to a line at anupstream end and a lumen; a spray tip at a downstream end having anorifice; means for mating the nozzle body with the spray tip, the matingmeans having a lumen and comprising a strainer having means forfiltering liquid passing through the mating means lumen, the strainerfurther having a strainer lumen in communication with the nozzle bodylumen and the spray tip orifice; and a plurality of bar magnetspositionable adjacent the spray tip along a liquid pathway, eachpositionable within the strainer, the bar magnets each having apositive/negative axis, a negative pole facing in a common direction forall bar magnets. wherein the spray tip, the coupling means, and thenozzle body comprise a substantially inert material.
 6. A system forspraying foliage comprising: a container for holding liquid and havingan opening; a nozzle comprising a spray tip at an upstream end andhaving an orifice and comprising an inert material and a magnet affixedadjacent the orifice along a liquid pathway; an additional magnetpositionable adjacent the container opening; a line having a lumen andaffixable at an upstream end to the container and affixable to thenozzle at a downstream end, the lumen in communication with thecontainer opening and with the nozzle orifice; and means for pumpingliquid from the container through the line and out the nozzle orifice.7. The system recited in claim 6, wherein the line comprises an inertmaterial.
 8. A system for spraying foliage comprising: a container forholding liquid and having an opening; a nozzle comprising a spray tip atan upstream end and having an orifice and comprising an inert materialand a magnet affixed adjacent the orifice along a liquid pathway; anadditional magnet positionable within the line; a line having a lumenand affixable at an upstream end to the container and affixable to thenozzle at a downstream end, the lumen in communication with thecontainer opening and with the nozzle orifice; and means for pumpingliquid from the container through the line and out the nozzle orifice.